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11.
A. V. Gorbatikov A. A. Il'inskii E. P. Krivtsov O. V. Pavlenko A. P. Yakovlev 《Measurement Techniques》1993,36(8):899-902
A set of standard equipments is considered for reproducing seismic oscillation parameters that have been developed at the Mendeleev All-Union Metrology Research Institute.Translated from Izmeritel'naya Tekhnika, No. 8, pp. 36–38, August, 1993. 相似文献
12.
T. I. Voronina T. S. Lagunova M. P. Mikhaĭlova K. D. Moiseev A. F. Lipaev Yu. P. Yakovlev 《Semiconductors》2006,40(5):503-520
The results of detailed study of the magnetotransport properties of broken-gap type II heterojunctions in a GaInAsSb/InAs(GaSb) system are reported. An electron channel with a high charge-carrier mobility (as high as 50000–60000 cm2/(V s)) is observed and studied for the first time in an isotype broken-gap p-GaInAsSb/p-InAs heterostructure. The effects of electron-channel depletion and semimetal-semiconductor transition in the case of heavy doping of the quaternary alloy with acceptors are studied. Magnetotransport properties at temperatures of 4.2–200 K are studied in detail. Data on the energy spectrum and parameters of two-dimensional charge carriers at the heteroboundary are obtained. It is ascertained experimentally that, depending on the composition, either staggered (at x = 0.85) or broken-gap (at x = 0.95) heterojunctions can be formed in the Ga1?x InxAsySb1?y /GaSb, which is confirmed by theoretical calculations. The anomalous Hall effect and negative magnetoresistance were observed in GaInAsSb/InAs:Mn grown on substrates doped heavily with Mn magnetic acceptor impurity so that the hole concentration was as high as p > 5 × 1018 cm?3; these phenomena are caused by exchange interaction of Mn ions in InAs with high-mobility charge carriers in the electron channel at the heterointerface. 相似文献
13.
For metal-insulator-semiconductor structures, a technique is described of analyzing the normalized conductance measured as a function of frequency with regard to the random variation of surface potential and the presence of electrically active states inside the insulator. Parameters are selected that are to be used in evaluating the amount by which the conductance-frequency characteristic is broadened. Analytical expressions are derived for the parameters. A method is proposed for separating the respective contributions of the tunneling and fluctuation mechanisms of the broadening. It enables one to evaluate the depth of the electrically active states and the variance of the surface potential when the two factors make comparable contributions to the inhomogeneity of the insulator-semiconductor interface. 相似文献
14.
P. N. Borutskii I. A. Volkov V. Yu. Georgievskii G. V. Stavrova A. A. Yakovlev T. G. Dolzhenkova 《Chemistry and Technology of Fuels and Oils》1990,26(8):390-392
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 8, pp. 7–8, August, 1990. 相似文献
15.
F. I. Yakovlev 《Metal Science and Heat Treatment》1988,30(9):706-709
1. | Kinetics for -transformation are governed by the silicon content in HC, redistribution of silicon between austenite and ferrite, and cast iron heating rate. This dependence expands the transformation range and causes formation of austenite which is inhomogeneous with respect to carbon and silicon concentration. |
2. | A dependence has been established for the temperature for the start and finish of austenite formation on silicon content in HC and its heating rate. The kinetic diagram plotted makes it possible to select a schedule for high-speed heating of castings for hardening with a given silicon content. |
16.
James King Sergey Yakovlev Zhisong Fu Robert M. Kirby Spencer J. Sherwin 《Journal of scientific computing》2014,60(2):457-482
Numerical methods for elliptic partial differential equations (PDEs) within both continuous and hybridized discontinuous Galerkin (HDG) frameworks share the same general structure: local (elemental) matrix generation followed by a global linear system assembly and solve. The lack of inter-element communication and easily parallelizable nature of the local matrix generation stage coupled with the parallelization techniques developed for the linear system solvers make a numerical scheme for elliptic PDEs a good candidate for implementation on streaming architectures such as modern graphical processing units (GPUs). We propose an algorithmic pipeline for mapping an elliptic finite element method to the GPU and perform a case study for a particular method within the HDG framework. This study provides comparison between CPU and GPU implementations of the method as well as highlights certain performance-crucial implementation details. The choice of the HDG method for the case study was dictated by the computationally-heavy local matrix generation stage as well as the reduced trace-based communication pattern, which together make the method amenable to the fine-grained parallelism of GPUs. We demonstrate that the HDG method is well-suited for GPU implementation, obtaining total speedups on the order of 30–35 times over a serial CPU implementation for moderately sized problems. 相似文献
17.
V. V. Sil’vestrov A. V. Plastinin I. V. Yakovlev V. V. Pai 《Combustion, Explosion, and Shock Waves》1997,33(3):360-377
Results of a study of hypervelocity impact in model disperse-reinforced composites with an epoxy or aluminum matrix with metallic
(Al and Pb) or ceramic (SiO2) inclusions are reported. The goal of the present study is to find materials that possess a higher resistance to penetration
of a high-velocity projectile compared with materials of separate components. This resistance is characterized by the ratio
of the depth of a crater in a sufficiently thick target to the diameter of a spherical projectile. For two composites studied,
we show that in impact of a steel particle with a velocity ranging from3 to11km/sec, the crater depth is approximately one projectile diameter smaller than that for lead or aluminum targets.
Lavrent’ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Fizika Goreniya i Vzryva, Vol. 33, No. 3, pp. 139–151, May–June, 1997. 相似文献
18.
K. K. Zabello I. N. Poluyanova V. V. Yakovlev S. M. Shkol’nik 《Technical Physics Letters》2017,43(11):1005-1008
It has been shown that such cathode spot characteristics as the average current per spot and its dependence on tangential magnetic-field induction B t and the spot velocity and its dependence on B t for two CuCr50/50 specimens with very different structures (nanocomposite and “solid-state sintered” composite) almost coincide if the surface of contacts has been totally remelted before measurements with the use of moderate arc currents in the process of conditioning. 相似文献
19.
20.
A. D. Kashtanov V. S. Lavrukhin V. G. Markov V. A. Yakovlev S. N. Bozin V. N. Leonov B. S. Rodchenkov A. I. Filin 《Atomic Energy》2004,97(2):538-542
Corrosion-mechanical tests of 10Kh15N9S3B and 10Kh9NSMFB steel samples in liquid lead at 360–550°C have shown that the long-time strength in lead flow decreases at short times to fracture and converges to the results of tests performed in air at about 10000 h. No liquid-metal embrittlement of 10Kh15N9C3B steel is observed. 10Kh9NSMFB steel becomes brittle in the hardened state. Embrittlement intensifies in notched samples. The low-cycle fatigue strength is correlated with a change in ductility with short-time fracture. No decrease of fracture toughness of 10Kh9NSMFB steel with a fatigue crack was observed in tests in liquid lead. 相似文献